1. Technical Field
The present invention relates generally to thrust control assemblies of the type employed in aircraft for controlling forward, idle and reverse thrust conditions of multi-engine aircraft; and, more particularly, to a simple, compact, modular, multiple engine thrust control assembly of the type wherein manual manipulation by the pilot of multiple side-by-side thrust control levers serves to drive a corresponding number of resolvers in an electric/electronic thrust engine control system. In accordance with the invention, n (wherein "n" may be 2, 3 or 4) manually manipulable pilot operated thrust control levers are mounted in closely adjacent side-by-side relation and are coupled through relatively simple linkage mechanisms of differing dimensions to respective ones of n conventional resolvers with such resolvers being mounted one above the other within a compact, narrow, above-floor housing so as to minimize weight and volume requirements; and, wherein each of the n thrust control levers can be shifted between: (i) intermediate forward and reverse idle positions and (ii) maximum forward or maximum reverse thrust positions; yet, wherein movement from an intermediate idle position to either the forward or reverse thrust position is inhibited until the multiple engines are properly configured for forward thrust on the one hand and reverse thrust on the other. The compact, modular, multiple engine, manually manipulable thrust control assembly further permits of automatic operation of the aircraft engines.
2. Background Art
In most conventional thrust control systems for multi-engine aircraft, manual positioning of multiple throttle controls by the pilot is effected through suitable cables, linkages and mechanical actuators to permit the pilot to throttle the aircraft engines between intermediate idle and full forward or full reverse thrust conditions. However, such conventional mechanical systems require extensive complex linkages and mechanical, electromechanical and/or fluid actuating mechanisms for positioning the engine control elements; and, unfortunately, such mechanisms are relatively heavy, space-consuming, and require extensive maintenance and service. In some instances, the pilot is required to utilize separate manually positionable control levers for establishing the forward and reverse thrust operational modes for each of the multiple engines such, for example, as in the system described in U.S. Pat. No. 3,321,921-Criffield. In other instances, a single control lever may be employed for controlling all operational thrust conditions for a given engine. A typical example of the latter approach is disclosed in U.S. Pat. No. 2,789,418-Machlanski. However, regardless of which prior approach is employed, the various mechanical linkages and drive mechanisms associated with the pilot-operated thrust control levers located in the cockpit are generally quite complex, heavy, and space-consuming.
Recently, serious consideration has been given to employment of electric/electronic engine thrust control systems suitable for use with multiple engine aircraft wherein actuation of the various aircraft controls--e.g., flaps, spoilers, engines, thrust reversers, etc.--is accomplished by manipulating control levers which serve to drive resolvers, switches and similar electric/electronic devices for positioning of such aircraft control elements. The present invention relates to an improved modular thrust control lever assembly for multiple engine aircraft which is characterized by its simplicity and compactness, which is light in weight, and which permits of ease of manufacture, installation and maintenance.